19 * This wiki will be undergoing lots of changes throughout the semester, and particularly in these first few days as we get it set up, migrate over some of the content from the previous time

20 we taught this course, and iron out various technical wrinkles. Please be patient. When you sit down to read the wiki, it's a good idea to always hit "Refresh" in your browser to make sure you're reading the latest additions and refinements of the website. (Sometimes these will be tweaks, other times very substantial. Updates will happen at miscellaneous hours, sometimes many times in a given day.)

22 If you're eager to learn, though, you don't have to wait on us to be ready to serve you. You can go look at the [archived first version](http://lambda1.jimpryor.net) of this course. Just keep in mind that

23 the text and links there haven't been updated. And/or you can get started on installing the software and ordering some of the books.

25 * As we mentioned in class, if you're following the course and would like to be emailed occasionally, send an email to <mailto:jim.pryor@nyu.edu>, saying "lambda" in the subject line. Most often, we will just post announcements to this website, rather than emailing you. But occasionally an email might be more appropriate.

28 * As we mentioned in class, we're also going to schedule a session to discuss the weekly homeworks. If you'd like to participate in this, please complete [this Doodle poll](http://doodle.com/7xrf4w8xq4i9e5za). It asks when you are available on Tuesdays and Wednesdays.

40 * Here is information about [[How to get the programming languages running on your computer|installing]]. If those instructions seem overwhelming, note that it should be possible to do a lot of this course using only demonstration versions of these languages [[that run in your web browser|browser]].

101 > Also, if you're reading the Hankin book, try reading Chapters 1-3. You will most likely need to come back again and read it multiple times; but this would be a good time to make the first attempt.

116 > Also, by this point you should be able to handle all of *The Little Schemer* except for Chapters 9 and 10. Chapter 9 covers what is going on under the hood with `letrec`, and that will be our topic for next week. You can also read Chapter 4 of Hankin on Combinatory Logic.

142 > *There is some assigned reading for our next meeting.* This comes in two batches. The first batch consists of [[this footnote|readings/kaplan-plexy.pdf]] from Kaplan's *Demonstratives*. Also recommended, but not mandatory, is [[this selection|readings/king-on-schiffer.pdf]] from Chapter 4 of Jeff King's 2007 book *The Nature and Structure of Content*. The second batch consists of [[this paper|readings/rieppel-beingsthg.pdf]] from Michael Rieppel, a recent Berkeley Philosophy PhD, on Frege's "concept horse" problem. Also recommended, but not mandatory, is [[this selection|readings/king-on-logicism.pdf]] from Chapter 5 of King's book. (It reviews and elaborates his paper "[Designating propositions](http://philpapers.org/rec/KINDP)".)

148 > If you're reading along in the Pierce book, the chapters most relevant to this week's discussion are 22 and 23; though for context we also recommend at least Chapters 8, 9, 11, 20, and 29. We don't expect most of you to follow these recommendations now, or even to be comfortable enough yet with the material to be able to. We're providing the pointers as references that some might conceivably pursue now, and others later.

170 > Updated notes on [[Installing and Using the Juli8 Libraries|/juli8]] on Sun 5 April. Continued to fix some bugs and improve the monad transformers. Latest version posted Monday evening, 13 April: [[v1.6|/code/Juli8-v1.6.tgz]]. This version is needed to run [[the gsv2.ml code|/code/gsv2.ml]].

173 The major change is to make the Monad libraries easier to use. Now you can just use `Monad.Reader(struct type env = ... end)`; you don't need to furthermore ask for the `M` submodule of that generated module. Relatedly, the `List` and `Monad.List` modules are now different; the former has lots of list-related functions and the latter only the monadic interface. Similarly for `Option` and `Monad.Option`.

255 "Computer Science is no more about computers than astronomy is about telescopes." -- [E. W. Dijkstra](https://en.wikipedia.org/wiki/Edsger_W._Dijkstra) <small>(or Hal Abelson, or Michael Fellows; the quote's <a href="https://en.wikiquote.org/wiki/Computer_science">origins are murky</a>)</small>

383 It's not *mandatory* to purchase these for the class. But they are good ways to get a more thorough and solid understanding of some of the more basic conceptual tools we'll be using. We especially recommend the first three of them.

399 on [Amazon](http://www.amazon.com/Seasoned-Schemer-Daniel-P-Friedman/dp/026256100X). This is a sequel to The Little Schemer, and it focuses on mutation and continuations in Scheme. We will be covering those topics in the second half of the course.

412 * *The Haskell Road to Logic, Math and Programming*, by Kees Doets and Jan van Eijck, currently $22 on [Amazon](http://www.amazon.com/dp/0954300696) is a textbook teaching the parts of math and logic we cover in the first few weeks of Logic for Philosophers. (Notions like validity, proof theory for predicate logic, sets, sequences, relations, functions, inductive proofs and recursive definitions, and so on.) The math here should be accessible and familiar to all of you. What is novel about this book is that it integrates the exposition of these notions with a training in (part of) Haskell. It only covers the rudiments of Haskell's type system, and doesn't cover monads; but if you wanted to review this material and become comfortable with core pieces of Haskell in the process, this could be a good read.

413 (The book also seems to be available online [here](http://fldit-www.cs.uni-dortmund.de/~peter/PS07/HR.pdf).)

418 * *Computational Semantics with Functional Programming*, by Jan van Eijck and Christina Unger, currently $42 on [Amazon](http://www.amazon.com/dp/0521757606). We own this but haven't read it yet. It *looks* like it's doing the same kind of thing this seminar aims to do: exploring how natural language meanings can be understood to be "computed". The text uses Haskell, and is aimed at linguists and philosophers as well as computer scientists. Definitely worth a look.

437 * Another good book, covering a bit of the same ground as the Hankin and the Hindley &amp; Seldin, but focusing especially on typed lambda calculi, is *Types and Programming Languages*, by Benjamin Pierce, currently $77 hardback / $68 kindle on [Amazon](http://www.amazon.com/dp/0262162091). This book has many examples in OCaml. It seems to be the standard textbook for CS students learning type theory.

439 * The next two books focus on the formal semantics of typed programming languages, both in the "denotational" form that most closely corresponds to what we mean by semantics, and in the "operational" form very often used in CS. These are: *The Formal Semantics of Programming Languages*, by Glynn Winskel, currently $38 on [Amazon](http://www.amazon.com/dp/0262731037), and *Semantics of Programming Languages*, by Carl Gunter, currently $41 on [Amazon](http://www.amazon.com/dp/0262071436).